Fixture for use in electric line installation

ABSTRACT

A device enables ready, accurate and positive preliminary mounting of an electric line part in completely one operation without the need for any screwing operation, regardless of a change in the width and height of the channel flanges of a channel rail and also, enables ready and positive permanent securement of the electric line part, and which allows an operator to extremely easily, positively and efficiently carry out this type of operation without the need for any skill. The device includes a fixture body having a part attached to a channel rail, a bolt, and a clamp threadedly engaged with the bolt. The clamp includes a central nut, pivot pins mounted to the nut, a pair of right and left clamping elements pivotable about the horizontal pivot pins and a protrusion extending outwardly from one side of the nut. The fixture body has a guide plate at a location where the fixture body is attached to the channel rail. The protrusion is guidably received in a guide slot of the guide plate.

TECHNICAL FIELD

The present invention relates to a fixture for use in electric lineinstallation.

BACKGROUND ART

It is necessary to install a power cable, a telecommunication cable orother cables, and pipes (cable tubes) through which those cables passfrom a vertical zone (vertical direction) to a ceiling zone (horizontaldirection) in various buildings such as a factory, a business office, astore, a condominium, a warehouse, a station, a gymnasium and a theateras well as in various structures such as a tunnel, a subway, an elevatedrailway, an elevated road, and a bridge.

In such a ceiling zone, hanger bolts are mounted to the ceiling at fixedintervals to hold channel rails. Racks are placed on and extend acrossthe channel rails to guidably support cables or cable tubes. The racksare then secured to the channel rails. As an alternative, the cabletubes are directly placed on and extend across the channel rails held bythe hanger bolts. The cable tubes are then secured to the channel rails.The channel rail may be directly secured to the ceiling with its opening(slot) being directed downward.

In the vertical zone, the channel rails are secured to structural beams,girders or walls at fixed intervals and extend in a horizontaldirection. The racks or cable tubes extend across and are secured to thechannel rails.

The channel rail is also referred to as a "hanger rail", "duct channel,or "raceway". In either case, the racks and cable tubes must be securedto each channel rail at points where the racks and cable tubes intersectwith each channel rail. A number of securing operations are thusrequired to complete the installation. A substantial number of securingoperations are involved where it is necessary to secure small girders orpartitions to the racks, or to secure outlet boxes or other electricdevices or components to the channel rails.

To this end, there has been proposed a fixture for securing racks asdisclosed in Japanese utility model publication No. 5-19671. The priorart fixture comprises a fixture body having a through opening at alocation where the fixture body is attached to a channel rail, a boltextending through the through opening, and a rectangular slat includinga central, internally threaded hole adapted to receive the bolt. Theslat has a pair of long sides and a pair of short sides. The long sidehas a length equal to or greater than the distance between flanges ofthe channel rail. Diagonally opposite corners of the slat are cut in anoblique fashion. A spring is disposed between the fixture body and thehead of the bolt to thereby lift the bolt and the slat.

However, the prior art fixture presents the following problems.

(1) The slat is substantially long and has a length greater than thewidth of the fixture body. Handling of such a large slat is cumbersome.The orientation of the slat must be adjusted if a change in theorientation of the slat occurs due to contact with hands or articlesprior to use.

(2) Preliminary mounting requires two steps, one step of axiallypressing the bolt to move the slat below the channel flanges of thechannel rail, and the other step of rotating the bolt by 90 degrees toswing the slat in a direction perpendicular to the channel rail. Theseoperations are cumbersome. Also, an operator is subject to fatigue sincehis wrists are repeatedly twisted.

(3) Preliminary mounting requires a screwing operation. If the bolt isinadvertently rotated in a counterclockwise direction, the slat isdisengaged from the bolt and may drop in the channel rail. Removal ofthe bolt requires substantial effort and time and thus deterioratesefficiency. Also, where the channel rail has a downwardly directedopening, the operator is subject to injury if the slat and articles aredisengaged from the bolt and the fixture body and hit the operator'shead and face.

(4) Rotation of the slat is limited when the longitudinal front end ofthe slat is contacted with the inner walls of the flanges. The slat maynot be oriented at right angles to or may be obliquely engaged with thechannel rail, depending on the configuration of the inner flange walls.This retards rotation of the bolt and causes the slat to be raised in anoblique fashion. If this occurs, the slat can not firmly be secured tothe channel rail since a sufficient clamping area between the endsurfaces of the downwardly directed rail walls and the slat is notavailable.

To this end, the inventors of the present application proposed a fixturefor securing cable tubes as disclosed in EP 0553 765 A1.

The prior art fixture comprises a fixture body, a bolt extending throughthe fixture body, and a clamp threadedly engaged with the bolt. Theclamp includes a central nut, and a pair of right and left clampingelements pivotably mounted to the nut and pivotable about a horizontalaxis. Each clamping element has a clamping surface engageable with thelower surfaces of channel flanges, and stop surfaces extending upwardlyfrom the clamping surface and contacted between the channel flanges. Aspring is disposed between the head of the bolt and the fixture body tolift the clamp and the bolt. The fixture body has opposite side wallsadapted to clamp the stop surfaces of the right and left clampingelements to hold the clamp relative to the fixture body.

In the prior art, electric line parts can be preliminarily mounted byaxially pushing the bolt.

A problem with the prior art is that since the bolt constantly extendsupwardly from the fixture body, external force may cause inadvertentoperation of the clamp. Another problem is that the clamp is susceptibleto displacement if the side walls of the fixture body are not equal tothe distance between the stopper surfaces of the clamping elements. Asto the latter problem, a clamping force is barely created if a space isleft between the opposite side walls and the stop surfaces. In such acase, the clamp is likely to be displaced prior to use. If the bolt ispushed while the clamp is displaced, the clamp is inserted in an obliquefashion into the opening of the channel rail. On the other hand, anexcess amount of clamping force is created when the distance between theopposite side walls is too short. If this occurs, assemblage becomescumbersome. Also, the clamp may not be lowered even if the bolt isstrongly pushed.

In the prior art, the stop surfaces of the clamping elements are snuglyfit within the channel flanges of the channel rail. This arrangementinsures lifting of the clamp and prevents rotation of the clamp about avertical axis during a clamping operation.

The distance between the channel flanges of the channel rail to besecured has effect on vertical upward motion of the clamp and rotationof the clamp about a vertical axis. A problem also arises when theheight of the channel flanges differ from each other, or when the clampis not appropriately positioned relative to the bolt even if the channelopening has a required width. In other words, the stop surfaces areundesirably moved below the lower ends of the channel flanges to causepivotal motion of the clamp about a vertical axis during a clampingoperation. This makes it difficult to orient the clamp at right anglesto the channel flanges. To this end, it is conventionally necessary toprepare various types of clamps to accommodate various types and sizesof channel rails to be secured. Also, it is necessary to carefully mountthe clamp to the bolt during assembly of the fixture.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a fixture whichenables ready, accurate and positive preliminary mounting of electricline parts in completely one operation without the need for any screwingoperation, regardless of a change in the width and height of channelflanges of a channel rail and also, enables ready and positivesubsequent permanent securement, and which allows an operator toextremely easily and positively carry out this type of operation withoutthe need for any skill.

It is a further object of the present invention to provide a fixture forinstalling electric lines, which allows for strong clamping of electriclines parts.

According to the present invention, "electric line parts" include arack, a main girder, a small girder or other girders, a partition orother separators, an outlet box or other devices, a cable, a cable tubeor similar tubes of various shapes and structures for securement to achannel rail during electric line installation.

In order to achieve the foregoing objects, a fixture according to theprimary feature of the present invention comprises a fixture body havinga through opening at a location where the fixture body is attached to achannel rail, a bolt extending through the through opening, and a clampthreadedly engaged with the bolt.

The fixture body includes a guide plate having a length such that it maybe inserted into the channel inlet of the channel rail. The guide platehas a vertical guide slot.

The clamp includes a central nut, pivot pins mounted to the nut, and apair of right and left clamping elements pivotable about the horizontalpivot pins. Each of the clamping elements has a clamping surface andguide surfaces extending upwardly from the clamping surface. The clampalso has a protrusion extending outwardly from one side of the nut andfit within the guide slot of the guide plate.

According to this primary feature, the guide plate is integral with thefixture body. In this case, the guide plate is bent from and oriented atright angles or near right angles to the front end of a portion (seatingportion or main portion) of the fixture body attached to the channelrail. Alternatively, the guide plate may be bent from and oriented atright angles or near right angles to the lower plate of the fixture bodywhich is turned rearwardly from the front end of a portion of thefixture body attached to the channel rail.

According to a second feature of the present invention, there isprovided a combination of a fixture body and an auxiliary fixture body.The fixture body has a through opening at a location where the fixturebody is attached to a channel rail.

The auxiliary fixture body has a plate superimposed on a portion of thefixture body which is attached to the channel rail. A guide plate isconnected to the plate and has a length such that the guide plate may beinserted into the channel inlet of the channel rail. The guide plate hasa vertical guide slot.

The clamp has a protrusion extending outwardly from one side of the nutand fit within the guide slot in the auxiliary fixture body.

According to either of the primary and second features, two guide slotspreferably extend parallel to two respective protrusions although theremay be provided a single guide slot and a single protrusion. The twoprotrusions are preferably integral with the pivot pins.

The fixture body is classified into two different types. One type offixture body is independent of an electric line part and includes aclamping portion for clamping the electric line part. The other type offixture body is integral with an electric line part. The former is usedto secure electric line parts such as a main girder, a small girder, apartition, a cable tube or similar tubes, and a cable or the like. Thelatter is used to secure electric line parts such as an outlet box orother devices.

Not only a single clamp, but a plurality of clamps may be mounted to thefixture body. The clamp, even if the right and left clamping elementsare fully opened, has a length less than the width of the channel inletof the channel rail. Preferably, the clamp includes a return elementadapted to move the clamping elements automatically from their closedcondition to opened condition. Also, the clamp preferably includes aretainer adapted to retain the nut at a distance from the fixture bodyor auxiliary fixture body.

According to the present invention, the fixture body or the auxiliaryfixture body includes a guide plate extending in the height directionand having a guide slot. A protrusion extending from the clamp is fitinto the guide slot from the side. Accordingly, the clamp is free fromvibration in a to-and-fro direction as well as lateral direction and isheld such that the side of the clamp extends parallel to the guideplate.

Where the fixture body is independent of an electric line part, theelectric line part is placed on a channel rail. The fixture body is thenpressed against the channel rail. This completes preliminary mounting ofthe electric line part. Where the fixture body is integral with anelectric line part, preliminary mounting is effected simply by pressingthe electric line part toward the channel rail.

Thus, the guide plate and the clamp are inserted into the channel inletof the channel rail while the guide plate and the clamp are held in anintegral fashion. A biasing force is applied to the fixture body torotate the clamping elements of the clamp in a symmetrical fashion abouta horizontal axis and urge them toward each other when the clampingelements are brought into contact with channel flanges of the channelrail. The clamping elements are returned to their open conditionimmediately when the outer ends of the clamping elements are movedbeyond the lower ends of the pair of walls.

At this time, the clamping elements are free from vibration since,according to the present invention, the protrusion which extends fromthe nut is fit within the guide slot of the guide plate. Thus, theclamping elements will in no way be offset from their requiredorientation if the guide surfaces of the clamping elements fail tocontact the channel flanges. It is possible to effect preliminarymounting in completely one operation without the need to rotate or pushthe bolt.

Under the circumstances, the position of the fixture body on the channelrail is adjusted. The bolt is rotated after the fixture body has beenpositioned. The bolt is then inserted into the nut to thereby raise thenut and the clamp. At this time, the protrusion is fit within the guideslot. These elements serve as guides and hold the clamping elements suchthat the clamping elements are oriented at right angles to the channelrail as the clamping elements are lifted. As such, the clamping portionsare moved toward and strongly pressed against the lower surfaces of apair of walls to firmly clamp the electric line part to the channel railif the stop surfaces of the clamping elements are spaced away from thelower surfaces of the channel flanges.

A fixture according to the present invention is suitable for any channelrail as far as a channel inlet has a width and depth such that theclamping elements can be closed and opened. Mounting of the clamp to thefixture body does not require positioning of the bolt relative to theclamp. It is also not necessary to provide a wide variety of clamps.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view showing one example of electric lines to which thepresent invention is applied;

FIG. 2 is a perspective view showing one example of a fixture forinstalling electric lines according to the present invention;

FIG. 3 is a perspective view showing another example of a fixture forinstalling electric lines according to the present invention;

FIG. 4 is a front view, partly broken away, of a first embodiment of thepresent invention wherein a rack is secured;

FIG. 5 is a side view, partly broken away, of the first embodiment;

FIG. 6 is a transverse sectional view of the first embodiment;

FIG. 7 is a rear view, partly broken away, of the first embodiment;

FIG. 8 is a partial side view of a second embodiment of the presentinvention wherein a rack is secured;

FIG. 9 is a perspective view of an auxiliary fixture body for use in thepresent invention;

FIG. 10 is a partial side view of a third embodiment of the presentinvention wherein a rack is secured;,

FIG. 11-A is a side view, partly broken away, of the embodiment with amodified protrusion;

FIG. 11-B is a front view of the embodiment shown in FIG. 11-A;

FIGS. 12-A to 12-C are front views showing how a fixture body and aclamp are moved upon preliminary mounting to permanent securement;

FIG. 13-A is a side view, partly broken away, showing the manner ofpreliminary mounting by means of a fixture for securing racks accordingto the present invention;

FIG. 13-B is a side view, partly broken away, showing the manner ofpermanent securement;

FIG. 14 is a sectional view of a fixture for securing a cable or cabletube according to a first embodiment of the present invention;

FIG. 15 is a sectional view of a fixture for securing a cable or cabletube according to a second embodiment of the present invention;

FIG. 16 is a sectional view of a fixture for securing a cable or cabletube according to a third embodiment of the present invention;

FIG. 17-A is a side view, partly broken away, showing the manner ofpreliminary mounting by means of a fixture for securing a cable or cabletube according to the present invention;

FIG. 17-B is a side view, partly broken away, showing the manner ofpermanent securement;

FIG. 18 is a side view, partly broken away, of a fixture for securing acable or the like according to a fourth embodiment of the presentinvention;

FIG. 19 is a side view, partly broken away, of a fixture according tothe present invention wherein a main girder is permanently secured frominside;

FIG. 20 is a side view, partly broken away, of a fixture according tothe present invention wherein a small girder is permanently secured;

FIG. 21 is a side view, partly broken away, of a fixture for securing anoutlet box according to the present invention;

FIG. 22 is an exploded front view, partly broken away, of a clamp foruse in the present invention;

FIG. 23 is a side view, partly broken away, of a modified retainer;

FIG. 24-A is a front view of the clamp with a modified return element;and

FIG. 24-B is a front view of the clamp with another modified returnelement.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

The present invention will now be described by way of example withreference to the accompanying drawings.

FIGS. 1 to 3 show one example of installing electric lines by the use offixtures according to the present invention. The reference numeral Agenerally designates the fixture according to the present invention.Referring to FIG. 1, there is shown three electric lines, a firstelectric line E1, a second electric line E2, and a third electric lineE3.

4 designates a plurality of channel rails as support members. Thechannel rails 4 extend from a structure 48 parallel to and are spaced apredetermined distance away from each other. In a ceiling zone, thechannel rails 4 are suspended by hanger bolts 46 through hanger fittings45, as shown in FIG. 2. The hanger bolts 46 extend downwardly from theceiling and through opposite ends of each channel rail or are arrangedat given intervals along the length of the channel rail. In a verticalzone, the channel rails 4 are bolted or otherwise secured to thestructure 48, as shown in FIG. 3.

5a designates racks (main girders) as electric line supports which areplaced on and extend across the channel rails 4, 4. Each rack 5a may bein the form of a strip plate which is subjected to punching and has awide C-shaped section. In this embodiment, the rack 5a includes a pairof right and left rails 50, 50 each with upper and lower flanges 500,501, and channel rails 4' (transverse beams) extending between theserails 50, 50. The rack 5a is thus in the form of a ladder.

Referring to FIG. 2, 5b designates a small girder (partition). The smallgirder 5b serves to divide cables, cable tubes through which such cablesextend, or fluid conduits (hereinafter, referred to as "cable or thelike") on the rack 5a. The small girder 5b is in the form of a rail andhas a wide, lower girder seat 502. The small girder 5b extends acrossthe channel rails 4', 4' of the rack 5a.

In the embodiment shown in FIG. 2, the hanger bolts 46, 46 extenddownward so as to support lower channel rails 4, 4. A cables or the likeB extends across the lower channel rails 4, 4 and is directly securedthereto by fixtures A according to the present invention.

Each of the channel rails may be secured to the ceiling with its channelinlet directed downward and extend across the cable or the like B. Itis, of course, to be understood that this arrangement falls within thescope of the present invention.

FIGS. 4 to 7 show a first embodiment (hereinafter, referred to as a"first rack related embodiment") wherein fixtures according to the firstrack related embodiment are attached to the outer sides of the rack 5ato retain the rack 5a against vibration. FIG. 8 shows a secondembodiment (hereinafter, referred to as a "second rack relatedembodiment"). FIGS. 9 and 10 show a third embodiment (hereinafter,referred to as a "third rack related embodiment"). Also, FIGS. 12-A to12-C and FIGS. 13-A and 13-B show the manner in which preliminarymounting and permanent securement are effected by a fixture according tothe first rack related embodiment.

FIG. 14 shows a first embodiment (hereinafter, referred to as a "firstcable related embodiment") wherein the cable or the like B (in thisparticular embodiment, electric cables tubes or pipes) is secureddirectly to the channel rails 4, 4. FIG. 15 shows a second embodiment(hereinafter, referred to as a "second cable related embodiment"). FIG.16 shows a third embodiment (hereinafter, referred to as a "third cablerelated embodiment"). FIGS. 17-A and 17-B show the manner in whichpreliminary mounting and permanent securement are effected by a fixtureaccording to the first cable related embodiment. FIG. 18 shows a fourthembodiment of the present invention (hereinafter, referred to as a"fourth cable related embodiment") wherein a fixture according to thefourth cable embodiment is used to simultaneously clamp a plurality ofcables or the like B, B.

FIG. 19 shows an embodiment of the present invention (hereinafter,referred to as an "inside embodiment") wherein fixtures according to theinside embodiment are attached to the inner sides of the rack 5a toretain the rack against vibration. Also, FIG. 20 shows an embodiment ofthe present invention (hereinafter, referred to as a "small girderrelated embodiment") wherein fixture according to the small girderrelated embodiment is used to secure the small girder 5b to the channelrail 4' of the rack 5a. FIG. 21 shows an embodiment of the presentinvention (hereinafter, referred to as an "outlet related embodiment")wherein fixtures according to the outlet related embodiment are used tosecure an outlet box 5c.

Each of the embodiments will now be described in detail.

(Channel rail)

As shown in FIG. 4, the channel rail 4 includes a web 4a, and a pair ofopposite side walls 4b, 4b. A pair of channel flanges 40, 40 extendinwardly from the upper ends 4c, 4c of the side walls 4b, 4b andcollectively define an channel inlet 42. The channel inlet 42 has awidth W1 less than the distance W2 between the side walls 4b, 4b.

In FIG. 4, the channel flanges 40, 40 of the channel rail 4 are inclineddownward. However, the sectional shape of the channel rail 4 is notlimited thereto. As shown in FIG. 12, the channel flanges 40, 40 may beturned vertically downward. Although not shown, the channel flanges mayalternatively extend in a horizontal direction. Also, the channel railmay take any other sectional shapes.

(Overall Structure of Fixture)

In the first rack and cable related embodiments, a fixture A comprises afixture body 1, a bolt 2 extending through the fixture body 1 and havinga shank 21, a clamp 3 threadedly engaged with the shank 21 of the bolt2, and a retainer 6 adapted to limit the position of the clamp 3 in theheight direction after the clamp 3 has been mounted to the fixturebody 1. In these embodiments, the retainer 6 is in the form of aresilient member and disposed between the clamp 3 and the fixture body 1to urge the clamp 3 away from the fixture body.

In the second rack and cable related embodiments, a reinforcement plate13 is additionally employed to better withstand a clamping torque asshown in FIGS. 8 and 15. The reinforcement plate 13 needs not beemployed in the case that the fixture body 1 has a sufficient strength,or a large force is not required to secure the elements.

In the third rack and cable related embodiments, an auxiliary fixturebody 1' is used to better withstand a clamping torque as shown in FIGS.10 and 16 and associated with a clamp guide as will be described later.

(Fixture Body 1 and Related Components)

In either embodiment, the fixture body 1 is made of a ferrous metal, anonferrous metal such as aluminum and aluminum-base alloy, a nonmetalsuch as plastic, or a composite material such as metal/nonmetalcomposite.

In the first rack related embodiment, the fixture body 1 includes a mainportion 10 for abutting engagement with the rail 50 of the rack 5a, anda clamping portion 11 bent from the upper end of the main portion 10 forclamping engagement with the upper flange 500 of the rack 5a as shown inFIG. 5. A seating portion 12 is bent from the lower end of the mainportion 10 and placed on the channel rail 4. Preferably, ribs 100 extendfrom the clamping portion 11 to the seating portion 12.

In this embodiment, the seating portion 12 has two plates arranged oneabove the other as shown in FIGS. 4, 5 and 7. Specifically, the seatingportion 12 includes an upper plate 12a and a lower plate 12b bent fromthe front end of the upper plate 12a. A through opening 120 is formed inthe upper plate 12a and the lower plate 12b to receive the shank 21 ofthe bolt 2.

The lower plate 12b has recesses 123, 123. A guide plate 122 is bentfrom the lower plate 12b at an angle of approximately 90 degrees and mayor may not extend through the recesses 123, 123. The guide plate 122extends downwardly from the lower plate and has a width so that theguide plate 122 may be inserted into the channel inlet 42 of the channelrail 4. A guide slot (in this embodiment, a plurality of guide slots)124, 124 extends from the lower end of the guide plate 122 and has agiven height.

In the second rack related embodiment shown in FIG. 8, a fixture body 1has a seating portion 12 in the form of a single plate. A guide plate122 extends downwardly from the front end of the seating portion 12 andhas guide slots 124, 124 identical to those used in the first rackrelated embodiment. The seating portion 12 has a through opening 120. Areinforcement plate 13 has a through opening 130 in alignment with theopening 120 and is superimposed on the seating portion 12.

In the third rack related embodiment shown in FIG. 10, a fixture body 1has a seating portion 12 in the form of a single plate. The seatingportion 12 has a straight front end rather than a bent front end. Asshown in FIGS. 9 and 10, an auxiliary fixture body 1' includes a plate121 superimposed on the seating portion 12, and a guide plate 122 bentdownwardly from the front end of the plate 121. The seating portion 12has a through opening. The plate 121 has a through opening 120' inalignment with the through opening 120 of the seating portion 12. Theguide plate 122 has guide slots 124, 124 identical to those used in thefirst rack related embodiment.

Next, in the first cable related embodiment shown in FIG. 14, a fixturebody 1 includes a clamping portion 11 having a shape substantiallycomplimentary to the sectional shape of the cable or the like B, and aseating portion 12 integral with and extending forwardly from the lowerend of the clamping portion 11. In this embodiment, the seating portion12 has two plates arranged one above the other, an upper plate 12a and alower plate 12b bent from the upper plate 12a. A through opening 120extends through the upper and lower plates to receive the shank 21 ofthe bolt 2.

A guide plate 122 is turned downwardly from the lower plate 12b. Theguide plate 122 has guide slots 124, 124 identical to those previouslydescribed. The guide plate 122 must be located outside of the region ofthe clamping portion 11.

Preferably, the clamping portion 11 has a size such that it is fitaround one half of the circumference of the cable or the like B. One endof the clamping portion 11 opposite the seating portion may be flushwith or substantially flush with the seating portion 12. In thisembodiment, the clamping portion 11 has an extension 14 in order tofacilitate holding of the cable or the like B and insertion of the guideplate 122 into the channel rail 4. The extension extends from one end ofthe clamping portion at a location flush with or slightly above theseating portion 12 and terminates below the seating portion 12. Theextension 14 has a size so that it may be inserted into the channelinlet 42 of the channel rail 4. Preferably, the extension 14 is slightlyinclined and has an outwardly bent guide portion 1141 at its lower end.

In the second cable related embodiment shown in FIG. 15, a fixture body1 has a seating portion 12. A guide plate 122 extends downwardly fromthe front end of the seating portion 12 and has guide slots 124, 124identical to those used in the first rack related embodiment.

In the third cable related embodiment shown in FIG. 16, a fixture body 1has a seating portion 12 in the form of a single plate. The seatingportion has a straight front end rather than a bent front end. Anauxiliary fixture body 1' is superimposed on the seating portion 12 andis identical in structure to that shown in FIG. 9. Parts whichcorrespond to those shown in FIGS. 9 and 10 are given like referencenumerals and will not be described herein.

In the fourth cable related embodiment shown in FIG. 18, a fixture body1 includes a clamping portion 11. The clamping portion 11 has oppositecurved portions 11a, 11a, and a straight portion 11b extending betweenthe curved portions 11a, 11a. Two projections 11d, 11d extend fromopposite lateral sides of the straight portion 11b and have concaved orarcuate surfaces 11c, 11c.

The two projections 11d, 11d are downwardly bent at right angles to thebody and serve as a pair of spacers. The arcuate surfaces 11c, 11c ofthe projections and the curved portions 11a jointly constitute a clampand have a shape corresponding to the sectional shape of the cable orthe like B. Any number of projections 11d may be employed. For example,two projections may be arranged along the length of the straight portion11b to secure three conduits in position. Four conduits may be securedif three projections are employed.

Seating portions 12, 12 are located below and extend forwardly fromopposite sides of the clamping portion 11. Guide plates 122 are bentfrom the respective seating portions 12, 12 and have guide slots 124,124 similar to those described earlier. This fourth cable relatedembodiment is illustrative only. It may include a reinforcement plate orauxiliary fixture body, or may be identical in structure to the firstcable related embodiment.

In the inside embodiment shown in FIG. 19, a fixture body 1 is in theform of a plate and has a main portion 10 as a seating portion, and aclamping portion 11 formed in the rear end of the main portion 10 andcontacted with the flange 501 of the main girder 5a. The main portion 10has a through opening 120 intermediate its width. In this embodiment,the clamping portion 11 extends in an oblique direction. Also, in thisembodiment, a guide plate 122 is turned from the front end of the mainportion 10 and has guide slots 124, 124.

In the small girder related embodiment shown in FIG. 20, a fixture body1 is in the form of a plate and has a main portion 10 as a seatingportion, and a clamping portion 11 formed in the rear end of the mainportion 10 and contacted with the girder seat 502 of the small girder5b. The main portion 10 has a through opening 120. In this embodiment,the clamping portion 11 extends in a horizontal direction, but mayextend in an oblique direction as in the inside embodiment. In thisembodiment, a guide plate 122 is turned from the front end of the mainportion 10 and has guide slots 124, 124.

In the outlet related embodiment shown in FIG. 21, a fixture body 1 hasa main portion 10 in the form of a strip plate which is bolted, weldedor otherwise secured to the lower surface of the outlet box 5c. The mainportion 10 serves as a seating portion, extends outwardly from oppositelongitudinal ends of the outlet box 5c, and has a through opening 120intermediate its width as in the previous embodiment. Also, a guideplate 122 is turned from the front end of the main portion 10 and hasguide slots 124, 124. The fixture body 1 may be composed of two discretemembers and separated before a cable-receiving opening 530.

The inside embodiment, the small girder related embodiment and theoutlet related embodiment are illustrative only. They may, of course,include a rear guide plate 122 as shown best in FIG. 5, a reinforcementplate as shown best in FIG. 8, and an auxiliary fixture body as shownbest in FIGS. 9 and 10.

In either embodiment, the guide plate 122 has a width equal to or lessthan that of the channel inlet 42 of the channel rail 4. The guide plate122 has a lower end flush with or above the pivot pins and has a lengthsuch that the guide plate 122 may not reach the bottom of the channelrail when the seating portion 11 or the main portion 10 is seated on thechannel rail 4.

The bolt 2 may take any form provided that it includes the head 20 andthe shank 21. The bolt 2 may be of the type which is subject to fracturewhen torque reaches a given level.

(Clamp 3)

Referring to FIGS. 3, 7 and 22, the clamp 3 generally includes a pair ofright and left clamping elements 3A, 3A, and a nut 3B into which theshank 21 is threaded through the through opening 120. The right and leftclamping elements 3A, 3A are supported by the nut 3B through the pivotpins 8, 8 and are openable and closable when they are pivoted at anangle of approximately 90 degrees about an axis which extends in adirection transverse to vertical axis (axis of the bolt 2).

The clamping elements 3A, 3A and the nut 3B may be made of any suitablematerials including a ferrous metal, a nonferrous metal such as aluminumand aluminum-base alloy, a nonmetal such as plastic, or a metal/nonmetalcomposite. The clamping elements 3A, 3A and the nut 3B may be made bypressing, forging, injection molding or other processes.

The clamping elements 3A, 3A of the clamp 3 are normally opened to amaximum extent. The clamp 3 includes a return element 7 in order toinsure that the clamping elements 3A, 3A are returned to their fullyopened condition from a closed condition.

The distance between the outer ends of the clamping elements 3A, 3A inits fully opened condition corresponds to a length L of the clamp 3 (seeFIG. 6). The length L is greater than the width W1 of the channel inletof the channel rail 4 and is less than the distance W2 between thechannel flanges of the channel rail 4. For the purpose of convenience,the width of the clamp 3 is less than that of the channel inlet 42. Theclamp 3 should be suspended at a location outside of the proximal end ofthe clamping portion 11 so that the clamp 3 does not interfere when theclamping portion 11 of the fixture body 1 is brought into contact withthe flanges 500, 501 or the girder seat 502.

As shown in FIGS. 6, 7 and 22, each of the clamping elements 3A, 3Aincludes a web 3a and two flanges 3b, 3b extending upwardly fromopposite sides of the web 3a and has a C-shaped section. The flange andthe web jointly provide a clamping surface 31 in the upper outer end ofeach of the clamping elements 3A, 3A. The clamping surface 31 is forcedinto contact with a lower surface 41 of the channel flange 40 of thechannel rail 4.

As shown in FIG. 22, a projection 30 is an extension of each of theflanges 3b, 3b and extends upwardly from the clamping portion 31. Theprojections 30 have guide surfaces 300, 300 in a face-to-face relationto the channel flanges 40, 40 of the channel rail 4.

The nut 3B includes a central threaded hole 33 adapted to receive theshank 21 of the bolt 2. The nut 3B has a width substantially equal tothe distance between the clamping elements 3A, 3A. As shown in FIGS. 4and 6, the clamping elements 3A, 3A are symmetrically fit over the nut3B through their rear openings and journaled by the pivot pins 8, 8.

As a feature of the present invention, a plurality of or a singleprotrusion 8a extends from one side of the nut 3B of the clamp 3 and isreceived within the guide slot 124 of the guide plate 122.

In a preferred embodiment, the protrusion 8a is integral with the pivotpin 8. Specifically, the pivot pin 8 has a length such that it extendsoutwardly from each of the clamping elements 3A, 3A. The protrusion 8ais formed at the free end of the pivot pin 8.

In this example, each of the pivot pins 8, 8 has an enlarged stopper 80at its free end. The pivot pin 8 also has a head (divider) 81 spacedfrom the stopper 80 by a distance substantially equal to the thicknessof the guide plate 122. A guide pin 82 extends between the stopper 80and the head 81.

To mount the clamping elements 3A, 3A to the nut 3B, each of the pivotpins 8, 8 is inserted into the nut 3B until the head 81 is brought intocontact with one of the flanges of each clamping element. One end of thepivot pin 8 which extends from the other flange is then caulked to formanother, opposite head. The guide slot 124 is so formed as to align withthe guide pin 82 and has a width substantially equal to that of theguide pin 82.

According to the present invention, the protrusion 8a is not necessarilyintegral with each of the pivot pins 8, 8. It may be a discrete member.Referring specifically to FIGS. 11-A and 11-B, the pivot pins 8, 8 onlyprovide a connection between the nut 3B and the clamping elements 3A,3A. A protrusion 8a is fixed to the side wall of the nut between theright and left clamping elements 3A, 3A and includes a stopper 80 and aguide pin 82. In this case, the protrusion 8a is in the form of a headedpin. The guide pin 82 has a bent rear end welded to the side wall of thenut. Alternatively, the guide pin may be threaded into or caulked to theside wall of the nut. To this end, the guide plate 122 has a singleguide slot 124 intermediate its width. The guide slot 124 has a widthsubstantially equal to the diameter of the guide pin 82.

According to the present invention, the embodiment of FIG. 11 may becombined with the embodiment of FIGS. 5 to 8. Specifically, there may beemployed right and left protrusions formed in the pivot pins 8, 8 and aseparate, central protrusion. In such a case, the guide plate has threeguide slots.

The projection 8a, in two different forms, of the clamping element 3thus constructed is commonly used in each embodiment. Accordingly,corresponding parts used in the other embodiments are given likereference numerals and will not be described.

The clamp 3 will be described in more detail. The projections 30, 30 ofthe clamping elements 3A, 3A are rearwardly inclined at a given anglesince the height of the projections has no effect on their function.However, a portion of each projection 30 above the guide surface 300 mayextend on a straight line. To facilitate closing of the clampingelements 3A, 3A, the projections 30, 30 are inclined downward from theirtop toward the bottom when the clamping elements are in their openedcondition.

As shown in FIGS. 7 and 22, the web 3a of each of the clamping elements3A, 3A has an inclined surface 304 below the clamping portion 31. Theinclined surface 304 extends parallel to the downwardly inclined surfaceof the projection 30 or is inclined at an angle near the angle of thedownwardly inclined surface of the projection 30. This facilitatesclosing of the clamping elements 3A, 3A after they are contacted withthe top wall of the channel rail 4. Each of the webs 3a, 3a has avertical surface 303 extending from the upper end of the inclinedsurface 304 and terminating at the clamping surface 31. The inclinedsurface 304 and the vertical surface 303 may be curved rather than flat.

The inclined surface 304 of the web 3a has a lower end 306 whichcooperates with the nut 3B to limit the extent of opening of theclamping elements. To this end, the lower end 306 terminates shortlybefore the rear end of each of the flanges 3b, 3b as shown in FIG. 22.

The nut 3B has a rectangular head 370 as viewed in plan, and legs 371.The legs 371 extend from the head 370 and are narrower in a lateraldirection. The head 370 has an inclined or arcuate lower surface. Thelower surface is inclined at an angle substantially equal to that of theinclined surface 304 of the web 3a.

As shown in FIG. 22, the head 370 of the nut 3B has two transverse holes372, 372 at a location outside of the threaded hole 33. The flanges 3b,3b have openings 308, 308 at predetermined locations. To provide aconnection between the clamping elements 3A, 3A and the nut 3B, theopenings 308, 308 are aligned with the transverse holes 372, 372. Thepivot pins 8, 8 are then inserted through the openings and thetransverse holes 372, 372.

In this embodiment, the nut 3B has an inverted C-shaped section. Thethreaded hole 33 is defined by the wall of the head 370 and the boss 373formed in the head 370.

The lower end of the leg 371, when assembled as shown in FIG. 7,terminates at or extends below the lower end of each of the clampingelements 3A, 3A. The lower end 306 of the web is brought into contactwith a side 374 of the leg 371 when the clamping elements 3A, 3A areopened to a maximum extent. This blocks further opening of the clampingelements 3A, 3A and at the same time, accommodates load when a strongclamping force is applied to the clamping surfaces 31, 31.

(Return Element 7)

To positively provide a return force, the return element 7 is preferablymade of a resilient material such as springs and rubber.

The springs include a leaf spring. As shown in FIG. 22, the leaf springis bent to a V-shape. The leaf spring is mounted from the lower surfaceof the leg 371 of the nut 3B and contacted with the inclined innersurfaces of the webs 3a, 3a of the right and left clamping elements 3A,3A. In this embodiment, the nut 3B has a C-shaped section to provide apair of legs 371, 371. Advantageously, the legs 371, 371 serve asstopper walls.

Preferably, the leaf spring includes a central opening 70 sized to allowthe passing of the shank 21 of the bolt 2. Advantageously, such a leafspring is simple in structure and is readily mounted to the clamp 3.

A wire spring may alternatively be employed as shown in FIGS. 24-A and24-B.

FIG. 24-A shows a tension spring which has opposite ends secured to theflanges at a location below the pivot pins 8, 8 so as to pull the lowerregion of each of the clamping elements 3A, 3A. FIG. 24-B shows ahelical tension spring which has a few turns at its center. Oppositeends of the helical tension spring are secured to the flanges at alocation above the pivot pins 8, 8.

The tension spring may alternatively be located below the nut 3B andextend between the webs of the right and left clamping elements 3A, 3Afor securing purposes.

In lieu of the return element 7, a clamping region of the clampingelements 3A, 3A may have a greater mass. To this end, a weight made oflead or other materials may be attached to the clamping region.Alternatively, the inclined upper end (vertical surface) of the web 3bmay have a greater thickness.

(Retainer 6)

The retainer basically functions to regulate the effective length of thebolt 2 and to allow the clamping elements 3A, 3A to be smoothly movedtoward each other against the action of the return element 7, with theclamping elements being spaced a predetermined distance away from theseating portion 12 or the main portion of the fixture body 1, when theclamp 3 is forced into the channel rail 4.

A resilient element is normally used as the retainer 6. The resilientelement is disposed between the lower surface of the seating portion 12or the main portion 10 and the head of the nut 3B to urge the nut 3Baway from the seating portion. As such, the bolt 2 can positively beheld in the seating portion 12 or the main portion 10 if a lifting forceis applied to the clamp 3. Additionally, the retainer 6 is effective toprevent the bolt 2 from being loosened when it is being secured andafter it has been secured.

The resilient element includes a rubber or plastic tube and bellows, butis preferably in the form of a coil spring. For better pressure offset,the coil spring is preferably tapered or takes a barrel shape with theupper and lower ends being less in diameter than the middle portion asshown in FIG. 4.

The resilient element may be separated from the clamp 3. However, theresilient element is preferably incorporated into the clamp to form aclamp assembly. To this end, a boss 373 illustratively has a stopper orprojection 375 on its outer periphery as shown in FIG. 22. By thisarrangement, the front end of the resilient member is moved over theprojection 375 while the resilient member is rotated in a clockwisedirection. The front end of the resilient member is then seated on theupper surface of the head of the nut below the boss 373. A portion ofthe resilient element slightly rearwardly of its front end is broughtinto engagement with the underside of the projection 375 to integratethe resilient element and the clamp 3 together.

The retainer 6 may alternatively be in the form of a metallic or plasticsplit ring 60 or similar elements as the case may be. In such a case,the split ring 60 is laterally fit to the shank 21 immediately below themain portion 10 or the seating portion 12 after the shank 21 has beeninserted through the main portion 10 or the seating portion 12 of thefixture body 1. The spring ring has on its inner periphery an internalthread with one or two pitches.

The retainer may also be in the form of a pin such as a split pin. Stillalternatively, a resistive element such as a relatively week adhesive orresin may be used to fill the space between the shank 21 and the throughopening 120 or the space between the bolt head 20 and the upper surfaceof the main portion 10, seating portion 12 or bent portion 12'. Theresistive element is subject to fracture when the bolt is rotated.

Several embodiments of the present invention are illustrated in thedrawings, but the present invention is not limited thereto.

Referring to FIGS. 10 and 16, the plate 121 is superimposed on theseating portion 12. Alternatively, the plate 121 may be attached to thelower surface of the seating portion 12.

The clamping surface 31 of each of the clamping elements 3A, 3A does notnecessarily extend in a horizontal direction. It may be inclined at anangle corresponding to the angle of inclination of the channel flanges40, 40 in the case that the channel flanges 40, 40 are inclined.

The nut 3B may be solid in section. In such a case, a groove (not shown)may be formed between the leg 371 and the head 370 to allow the passingof the return element 7 below the leg 371 of the nut 3B. The grooveshould have a width corresponding to that of the return element 7.

Where the protrusion 8a is not formed as part of each of the pivot pins8, 8, a guide groove or recess may be formed in the side wall of the nut3B to receive the protrusion 8a. In such a case, a pin may be secured tothe guide plate 122.

Reference will next be made to the manner of use and operation of theembodiments of the present invention.

(Assembly)

Where the retainer 6 is a resilient element, and the nut 3B is providedwith the projection 375, the retainer 6 is connected to the nut 3Bthrough the projection 375 to form one assembly.

The retainer 6 is then brought into alignment with the through opening120 of the main portion 10 or the seating portion 12 of the fixturebody 1. The guide pin 82 of the protrusion 8a which extends from theclamp 3 is positioned within the guide slot 124 of the guide plate 122.In this state, the shank of the bolt 2 is inserted through the throughopening 120 into the threaded hole 33 of the nut 3B. The bolt 2 isrotated to compress the retainer 6. The bolt 2 continued to be rotateduntil a desired effective length of the shank is obtained to exert apredetermined lifting force on the clamp 3. As a result, the clamp 3 islifted to cause the guide pin 82 of the protrusion 8a to be received inthe guide slot 124.

Where the nut 3B is not formed with the projection 375, the retainer 6is a discrete member. To this end, the lower end of the retainer 6 isfit around the boss 373 of the nut 3B. In this state, the bolt 2 isbrought into alignment with the through opening 120 of the main portion10 or the seating portion 12. The rest of the operation is the same asabove.

Where the retainer 6 is configured as shown FIG. 23, the retainer is fitaround the shank 21 at a location below the main portion 10 or theseating portion 12 after the shank 21 has been threaded into the clamp 3through the main portion 10 or the seating portion 12.

In either case, the head 81 and the stopper 80 exist at opposite ends ofthe guide pin 82 in the clamp 3. These members have a large diameter andare located adjacent to the surface of the guide plate 122. As such, theclamp 3 can automatically be positioned in parallel to the guide plate122 and spaced a fixed distance away from the guide plate 122. Under thecircumstances, the clamp 3 is free from rotation and vibration if theclamp 3 is contacted by hands or other objects, and the guide plate isconstantly oriented at right angles to the guide slot 42 of the channelinlet 4. Also, the bolt 2 will in no way be rotated and will have arequired effective length. This results in ready assembly.

When the guide plate 122 is dependent behind the bolt as shown in FIGS.5 and 14, it is possible to instantaneously visually determine as towhether or not preliminary mounting is properly effected.

(Preliminary Mounting)

Reference will now be made to preliminary mounting of electric lineparts.

To preliminarily mount the rack 5a to the channel rail 4 from outside,the rack 5a is first placed on and extends across the channel rails 4.As shown best in FIG. 5, the fixture body 1 is positioned so that themain portion 10 extends along the outer surface of the rack 5a, and theclamping portion 11 is located above the bent portion 500. The fixturebody 1 is then pressed downward.

To preliminarily mount the cable or the like B, the cable or the like Bis first placed on and extends across the channel rails 4. As shown bestin FIG. 14, the fixture body 1 is positioned so that the extension 14 islocated adjacent to the cable or the like B, and the clamping portion 11is located above the cable or the like B. The fixture body 1 is thenpressed downward. Referring to FIG. 18, the fixture body 1 is presseddownward after the projection lid is located above the cable or the likeB. The fixture body 1 is then pressed downward.

To clamp the rack 5a from inside so as to retain it against vibration,the fixture body 1 is first held such that the clamping portion 11 islocated right above the bent portion of the rack 5a as shown by theimaginary line in FIG. 9. The fixture body 1 is then pressed downward.

To preliminarily mount the small girder, as a transverse beam for therack 5a, to the channel rail 4', the fixture body 1 is first held rightabove the girder seat 502 of the small girder 5b placed on the channelrail 4', as shown by the imaginary line in FIG. 20. The fixture body 1is then pressed downward.

To preliminarily mount the outlet box 5c to the channel rail or duct 4,the outlet box 5c is located right above the channel rail 4 and thenpressed against the channel rail 4.

As shown in FIG. 4, the bottoms or inclined surfaces 304, 304 of theclamping elements 3A, 3A in the clamp 3 which is suspended from theseating portion 12 or the main portion 10 are then brought into contactwith the top walls of the channel flanges 40, 40. Also, the lower end ofthe guide plate 122 faces against the opening or is slightly insertedinto the channel inlet.

Further downward movement of the fixture body 1 causes the guide plate122 together with the clamp 3 to be inserted into the channel inlet 42.The inclined surfaces 304, 304 (web 3a, 3a) are then pressed laterallyby the channel flanges 40, 40.

As a result, the right and left clamping elements 3A, 3A are inwardlypivoted about the pivot pins 8, 8 against the action of the returnelement 7, 7 as shown in FIG. 12-A. The entire assembly is lowered whilethe clamping elements are being moved toward each other with theinclined surfaces 304, 304 in contact with the channel flanges 40, 40.At this time, the clamp 3 and the bolt 2 will in no way be lifted sincethe biasing force of the retainer 6 is greater than that of the returnelement 7, 7. Accordingly, the clamping elements 3A, 3A can smoothly andpositively be moved toward each other.

When the fixture body 1 is further pressed downward, the seating portion12 or the main portion 10 is moved closer to the top walls 4c, 4c of thechannel rail. The clamping elements 3A, 3A are no longer clamped betweenthe channel flanges 40, 40 when the inclined surfaces 304, 304 of theright and left clamping elements 3A, 3A are moved beyond the lower endsof the channel flanges 40, 40.

As a result, the return element 7, 7 causes the clamping elements 3A, 3Ato be outwardly pivoted about the pivot pins 8, 8 as shown in FIG. 12-B.Then, the clamping portions 31, 31 are moved beyond the lower surfaces41, 41 of the channel flanges 40, 40. At this time, the projectionsadjacent to the clamping surfaces 31, 31, when rotated, have a radius ofcurvature substantially the same as that of the clamping portions 31,31. As such, the projections can smoothly be moved below the channelflanges 40, 40 of the channel rail 4 regardless of no matter how highthe channel flanges 40, 40 are.

Immediately after the projections are moved beyond the channel flanges40, 40, the clamping surfaces 31, 31 are held in a horizontal positionunder the influence of the return element 7. The guide surfaces 300, 300are then spaced from or contacted with the channel flanges 40, 40. Inthe embodiment shown in FIG. 21, the right and left clamps aresimultaneously operated in the same manner as thus far described.

Downward movement of the fixture body 1 is automatically stopped whenthe main portion 10 or the seating portion 12 of the fixture body 1 isbrought into contact with the top of the channel rail 4. At this time,the clamp portion 11 is engaged with the bent portion 500 of the rack5a, the outer surface of the cable or the line B or the seating portion502 of the small girder 5b.

When the clamping elements 3A, 3A are outwardly rotated as explainedearlier, the lower ends 306, 306 of the webs are brought into contactwith the sides 374, 374 of the legs in the nut 3B, respectively, and theclamping elements 3A, 3A are held in their fully opened condition. Atthis time, the free ends of the pivot pins 8, 8 are fit within the guideslots 124, 124 of the guide plate 122. Thus, the clamping elements 3A,3A are free from displacement and vibration in a lateral direction aswell as in a to-and-fro direction if strong shock occurs.

If the guide surfaces 300, 300 are not contacted with the channelflanges 40, 40 as shown in FIG. 12-C, or if the projections are locatedfully below the lower surfaces of the channel flanges 40, 40 as shown inFIGS. 13-A and 17-B, the clamping portions 31, 31 can be positioned in aface-to-face relation to the lower surfaces 41, 41 of the channelflanges 40, 40. This completes preliminary mounting.

Under the circumstances, the fixture body 1 is in no way separated fromthe channel rail 4 since the clamping portions 31, 31, if the fixturebody 1 is lifted, are brought into contact with the lower surfaces 41,41 of the channel flanges 40, 40 to hold the clamping elements 3A, 3A inan open condition. By the same token, the fixture body 1 is not subjectto lateral displacement since the lateral sides of the guide plate 122,if the fixture body 1 is moved in the lateral direction of the channelrail, are brought into contact with the channel flanges 40, 40.

On the other hand, the fixture body 1 is free to move along the channelinlet 42. At this time, the guide plate 122 is properly guided by itswidth. Also, the clamp 3 is free from displacement since the projection8a is fit within the guide slot 124. As such, the clamping portions 31,31 can be held at right angles to the lower surfaces 41, 41 of thechannel flanges 40, 40 if the fixture body 1 is moved. It is possible toreadily adjust the position of the fixture body 1 along the channel railwhile the fixture body 1 is placed around the rack 5a, the cable or thelike 5, or the small girder 5b. Referring to FIG. 21, the fixture body 1is free to move since the fixture body 1 is integral with the outlet box5c.

As thus far described, preliminary mounting does not require hanging ofthe fixture body 1 from the channel rail 4 and contact of the bolt 2. Itis thus possible for any operator to extremely easily carry outoperation without failure.

(Permanent Securement)

After the position of the fixture body 1 has been adjusted, the bolt 2is rotated. This rotation can easily be effected without displacement ofthe bolt 2 since the nut 3B is pressed downward by the retainer 6 topositively seat the head of the bolt 2 on the seating portion 12 or themain portion 10.

As the bolt 2 is rotated, the shank 21 is inserted into the nut 3B toinitiate upward movement of the clamp 3 against the biasing force of theretainer 6. Since the guide pin 82 of the protrusion 8a is fit withinthe guide slot 124 of the guide plate 122, the clamp 3 is in no wayrotated with the shank 21, inclined in a vertical plane, or displaced inthe width direction if the clamp 3 even as a whole is located below thechannel flanges 40, 40. The clamp 3 can therefore be lifted while it isheld exactly at right angles to the channel inlet 42 of the channel rail4.

The guide surfaces 300, 300 face against the channel flanges 40, 40while the clamping surfaces 31, 31 are in close contact with the lowersurfaces 41, 41 of the channel flanges 40, 40. This allows for strongclamping. At this time, the lower ends 306, 306 of the webs of theclamping elements 3A, 3A are held against the sides 374, 374 of the legsof the nut 3B. Thus, the clamping elements 3A, 3A withstand a highdegree of torque, are in no way unduly opened, and are positively heldin position. Where the nut 3B has a C-shaped section, the clampingelements withstand a high degree of torque since load is applied in thethickness and vertical directions.

A high degree of clamping torque can be applied in the case that theseating portion 12 or the main portion 10 is composed of the upper plate12a and the lower plate 12b, or the reinforcement plate 13 or theauxiliary fixture body 1' is superimposed on the seating portion 12 orthe main portion 10 to increase the strength.

When the guide plate is dependent behind the bolt as shown in FIGS. 5and 14, it is possible to visually determine as to whether or notclamping is proper.

In the first rack related embodiment, the second rack related embodimentand the third rack related embodiment, the rack 5a is strongly pressedagainst and permanently secured to the channel rail as shown in FIG.13-B while the clamping portion 11 is fit around the rack 5a. In thefirst to fourth cable related embodiments, the cable or the like B isstrongly pressed against the channel rail while the clamping portion 11is closely fit around the cable or the like B as shown in FIG. 17-B.

In the inside embodiment, the rack 5a is strongly pressed against thechannel rail by the clamping portion 11 as shown in FIG. 19. In thesmall girder related embodiment, the small girder 5b is strongly pressedagainst the channel rail by the clamping portion 11 as shown in FIG. 19.In the outlet related embodiment, the outlet box 5c is strongly pressedagainst the channel rail as shown in FIG. 20.

At this time, the retainer 6 is compressed between the seating portion12 or the main portion 10 and the nut 3B and cooperates with the clamp 3to strongly urge the bolt 2 in a downward direction. No loosening aftersecurement occurs.

A fixture for installing electric lines according to the presentinvention can be used to secure other instruments, devices or componentsto a channel rail. Also, it can be used as a means to secureinstruments, devices and components to an apertured plate.

We claim:
 1. A device for clamping electric line parts, comprising afixture body attachable to a channel rail and having a through openingat a location where said fixture body is to be attached to the channelrail, said fixture body including a guide plate at the location wheresaid fixture body is attachable to the channel rail, said guide plateincluding at least one vertical guide slot and having a size such thatsaid guide plate is insertable into a channel inlet of the channel rail;a bolt extending through said through opening of said fixture body; anda clamp threadedly engaged with said bolt, said clamp including acentral nut, substantially horizontal pivot pins mounted to said nut,and a pair of right and left clamping elements pivotable about saidpivot pins, each of said clamping elements including a clamping surfaceand guide surfaces extending upwardly from a proximal end of saidclamping surface, said clamp including at least one protrusion extendingoutwardly from one side of said nut and received within said guide slotof said fixture body so that said clamp is oriented in a fixed relationto said fixture body.
 2. A device as defined in claim 1, wherein saidguide plate has a plurality of said vertical guide slots.
 3. A device asdefined in claim 1, wherein said clamp has a plurality of saidprotrusions.
 4. A device as defined in claim 3, wherein said protrusionsare integral with free ends of said pivot pins.
 5. A device as definedin claim 1, wherein said fixture body has a lower plate at the locationwhere said fixture body is attachable to the channel rail, said guideplate being bent from said lower plate.
 6. A device as defined in claim1, wherein said fixture body has a portion attachable to the channelrail, said guide plate being bent from a front end of said portion.
 7. Adevice as defined in claim 1, wherein said protrusion extends from oneside of said nut between said pivot pins.
 8. A device as defined inclaim 1, wherein said protrusion has a front end and is provided with astopper and a guide pin at said front end.
 9. A device as defined inclaim 1, wherein said fixture body is provided with a clamping portionfor clamping the electric line part.
 10. A device as defined in claim 1,wherein said fixture body is integral with an electric line part.
 11. Adevice as defined in claim 1; and further comprising an electric linepart including at least one element selected from the group consistingof a rack, a girder, an electric cable tube, a partition and an outletbox.
 12. A device as defined in claim 1, wherein each of said pair ofsaid clamping elements of said clamp includes a web and flanges and hasa C-shaped section, said web having a lower end which is brought intocontact with a lower portion of said nut so as to limit an extent ofopening of said pair of said clamping elements.
 13. A device as definedin claim 1, wherein said clamp has a return element for urging said pairof said clamping elements such that said clamping elements canconstantly be opened, and a retainer for retaining said nut at a desireddistance from a lower surface of said fixture body.
 14. A device asdefined in claim 13; and further comprising an auxiliary fixture body,said retainer retains said nut at a desired distance from a lowersurface of said auxiliary fixture body.
 15. A device as defined in claim13, wherein each of said pairs of said clamping elements includes a weband flanges said return element including a leaf spring extending belowa lower part of said nut and between said webs of said clampingelements.
 16. A device as defined in claim 13, wherein said retainer isincorporated into said clamp so as to form a clamp assembly.
 17. Adevice as defined in claim 13, wherein said retainer has a coil spring,said nut having a head provided with a projection, said retainer havinga lower end secured onto said projection.
 18. A device as defined inclaim 1, wherein said clamp is attachable to either side of said fixturebody.
 19. A device as defined in claim 1, wherein said fixture body hasan extension at a side which is opposite to a side of said fixture bodywhich is attachable to the channel rail, said extension having a widthso that said extension is insertable into the channel rail.
 20. A devicefor clamping electric line parts onto a channel rail, comprising afixture body having a through opening at a location where said fixturebody is attachable to a channel rail; a bolt extending through saidthrough opening of said fixture body; an auxiliary fixture body having aplate superimposed on a portion of said fixture body, said auxiliaryfixture body including a guide plate extending from said plate andhaving at least one vertical guide slot and a length such that saidguide plate is insertable into a channel inlet of the channel rail; anda clamp threadingly engaging said bolt, said clamp including a centralnut, substantially horizontal pivot pins mounted to said nut, and a pairof right and left clamping elements pivotable about said pivot pins,each of said clamping elements having a clamping surface and guidesurfaces extending upwardly from a proximal end of said clampingsurface, said clamp having at least one protrusion extending outwardlyfrom one side of said nut and received within said guide slot so thatsaid clamp is oriented in a fixed relation to said fixture body.
 21. Adevice as defined in claim 20, wherein said guide plate includes aplurality of said vertical slots.
 22. A device as defined in claim 20,wherein said clamp includes a plurality of such protrusions.
 23. Adevice as defined in claim 22, wherein said protrusions are integralwith free ends of said pivot pins.
 24. A device as defined in claim 20,wherein said protrusion extends from one side of said nut between saidpivot pins.
 25. A device as defined in claim 20, wherein said protrusionhas a front end and is provided with a stopper and a guide pin at saidfront end.
 26. A device as designed in claim 20, wherein said fixturebody is provided with a clamping portion for clamping the electric linepart.
 27. A device as defined in claim 20, wherein said fixture body isintegral with an electric line part.
 28. A device as defined in claim20; and further comprising an electric line part including at least oneelement selected from the group consisting of a rack, a girder, anelectric cable tube, a partition and an outlet box.
 29. A device asdefined in claim 20, wherein each of said pair of said clamping elementsof said clamp includes a web and flanges and has a C-shaped section,said web having a lower end which is brought into contact with a lowerportion of said nut so as to limit an extent of opening of said pair ofsaid clamping elements.
 30. A device as defined in claim 20, whereinsaid clamp has a return element for urging said pair of said clampingelements such that said clamping elements can constantly be opened, anda retainer for retaining said nut at a desired distance from a lowersurface of said fixture body.
 31. A device as defined in claim 30,wherein each of said pairs of said clamping elements includes a web andflanges, said return element includes a leaf spring extending below alower part of said nut and between said webs of said clamping elements.32. A device as defined in claim 30, wherein said retainer isincorporated into said clamp so as to form a clamp assembly.
 33. Adevice as defined in claim 32, wherein said retainer has a coil spring,said nut having a head provided with a projection, said retainer havinga lower end secured onto said projection.
 34. A device as defined inclaim 20; and further comprising an auxiliary body, said retainerretains said nut at a desired distance from a lower surface of saidauxiliary fixture body.
 35. A device as defined in claim 20, whereinsaid clamp is attachable to either side of said fixture body.
 36. Adevice as defined in claim 20, wherein said fixture body has anextension at a side which is opposite to a side of said fixture bodywhich is attachable to the channel rail, said extension having a widthso that said extension is insertable into the channel rail.